Currently, conveyor systems utilize rollers supported at each end by side frame members. It is common for the rollers to be supported on bearings mounted onto axles having a hexagonal cross section. The axles are then inserted into hexagonal openings formed in the frame members. The hexagonal cross section prevents rotation of the axle in the frame and rotation of the bearing inner race on the axle. Typically, the axles and side frame members will be made from metal. It is also typical for the axle to fit somewhat loosely into the opening in the side frame to allow for ease of assembly and slight misalignments between the side frame members. This arrangement for mounting the rollers to the side frame creates problems with both noise generated by the conveyor system, and wear of the axles and side frame members.
Because of the metal-to-metal contact between the axle and side frame member, noise generated by rotation of the rollers is easily transmitted to and amplified by the side frame members. Additional noise is generated by the loose fit between the axle and the side frame members. The combined effects of noise transmitted from the rollers to the side frame members and noise generated at the mount interface between the axle and the frame can create a serious problem for users of conveyor systems.
Additionally, the metal-to-metal contact between the axles and the side frame members generates wear in both the axle and the openings in the side frame members. This problem is most severe when the axle has a loose fit within the opening, which allows for relative motion between the axle and the side frame member each time an article is conveyed over the roller. Even when the axle is mounted with a tight fit to the opening, wear is generated in the metal-to-metal contact due to fretting as articles are conveyed over the roller. Replacement of worn conveyor components, especially the side frame members, can be expensive due to the cost of replacement parts, the cost of assembly, and the down time of the conveyor system.
One current attempt at solving the problem of noise and wear in a conveyor system involves the use of customized side frame members in a multi-piece bearing block made from nylon or synthetic resin. This is expensive and not easily adaptable to standard conveyor systems.
There is a need for a new and inexpensive apparatus for mounting conventional conveyor rollers to conventional conveyor side frame members to prevent wear and to reduce noise levels generated by articles being conveyed over the rollers.